There are so many examples of passive card draw, and these types of effects dominated in the First Chapter metagame because they were often a better payoff than their active cousins (and there were less active ones at the time)
The value of X is calculated only once, as Heidegger's first ability resolves
Theres also no guarantee that this is the only Japanese exclusive treatment for the Final Fantasy MTG set
It triggers whenever you play a land, as well as whenever a spell or ability puts a land onto the battlefield under your control
A Japanese Exclusive This Force of Negation is already absurdly rare for MTG standards, but its going to be even more difficult to get for American players
Rafiki, Mysterious Sage Hit your opponent before they have a chance to react The Lion Kings wise mandrill takes a surprising preference for brawn over brains in Lorcana, striking your opponents with solid attack power before they can do much about it